Contact-line mobility characterizes how fast a liquid can coat or uncoat a substrate support. During rapid movement of liquid across a supporting substrate, contact angles and contact line speeds change dynamically. Mobility captures this far-from-equilibrium behavior. For sufficiently rapid movement, the flow is largely inviscid and surface tension and liquid inertia compete to influence the interface shape near the support.
While standard goniometry techniques address the issue of determining the static contact angle and the contact angle hysteresis of a substrate-liquid-gas system, there is no current standard for measuring the mobility of the contact line in terms of the velocity dependence of the contact angle.
There is a need for new and improved technologies for measuring contact-line mobility of inertially spreading liquids.
The present invention is directed to overcoming these and other deficiencies in the art.